Comparative analysis between axial and coaxial magnetic couplings

The adoption of magnetic couplings enables the transmission of mechanical power relying on the magnetic fields' interaction rather than a physical mechanical connection. Hence, the contactless speed/torque transmission leads to improvements in terms of efficiency and reliability, due to the absence of wear out between moving parts. For a specific application, the most appropriate magnetic coupling configuration (i.e. axial or coaxial) is usually identified through a trade-off study. In this paper, a comparative analysis between axial and coaxial magnetic couplings is presented using a two-dimensional subdomain approach. Based on a full-parametric geometry, two 2D analytical tools are developed for each magnetic coupling configuration. These analytical tools are validated against finite element results in order to prove their effectiveness. Finally, the implemented models are used to investigate the impact of parameters, such as permanent magnet span, airgap thickness and number of pole-pairs, on the maximum static torque.